Caster assembly for a convertible floor cleaning machine



y 1969 c. w. WALTHER 3,452,380

CASTER ASSEMBLY FOR A CONVERTIBLE FLOOR CLEANING MACHINE Filed June 5. 1967 INVENTOR. BE URE'E W. WAL THE'R.

BY @9 @La .21 T Tys,

United States PatentO US. Cl. 15-49 2 Claims ABSTRACT OF THE DISCLOSURE A caster assembly is provided for supporting a carpet cleaning machine above a surface being cleaned, with the only weight on the scrubbing brush bristles being the weight of the brush itself. Heretofore, floor scrubbing machines have been used to shampoo carpets, in which instance, casters have been screwed or similarly fastened to the skirt of the floor scrubbing machine to partly support the weight thereof independently of the brush. Attaching and later removing the casters was a time consuming operation and in addition required that special openings be located in the skirt of the scrubbing machine to accommodate the fasteners. The new caster assemblies, however, can be assembled with the machine simply by placing them over the lower edge of the skirt. If desired, the assemblies can be kept from dropping off the skirt by a rubber bumper ring extending around the periphery. With this arrangement, the caster assemblies can be attached and removed in a matter of a few seconds, without any tools and without the necessity of forming special holes in the skirt.

This invention relates to a detachable caster assembly for easy attachment to and removal from a load to be supported, and more particularly to such a caster assembly for aiding in supporting a floor scrubbing machine in applications where the weight of the machine is to be at least partially supported independently of the cleaning tool rotatably supported thereby.

Floor scrubbing machines usually employing one or two rotating scrub brushes are commonly used to clean large floor areas. In many instances, these machines can also be used to clean carpeting. Where the machines are employed to clean floors, the weight of the machine is supported on the brush or brushes for increased pressure and improved cleaning. Where the machines are employed to shampoo or clean carpeting and softer or more flexible bristles are used, however, it is desirable that the weight of the machine not be carried directly on the brush but be independent thereof so that substantially the only weight on the bristles is that of the brush itself. For the above purpose, several casters have heretofore been affixed to the skirt of the floor cleaning machine with the casters being designed to support the weight of the machine directly on the floor and yet enable the brush to contact the floor, The brush is driven through a connection which enables it to float, so that the weight of the brush itself is the only weight on the bristles.

The casters previously employed have been attached to the skirt of the machine by screws or similar fasteners. Of necessity, such fasteners have rendered the process of affixing and removing the casters rather time consuming. Further, tools were required for this purpose which were not always readily available, and the fasteners were subject to being lost. The skirt also had to be specially drilled or otherwise machined to receive the fasteners, which added to the difficulties.

The present invention provides a unique caster assembly by means of which the casters can be easily attached to and removed from the skirt of the floor machine. The casters can be attached without the use of special tools 3,452,380 Patented July 1, 1969 and without the necessity of special drilling or machining of the skirt. The unique caster assembly includes a supporting bracket having an upstanding flange which cooperates with the caster housing and bears against the skirt when the caster is supporting the machine. The bracket further includes tabs or hooks which extend under the bottom edge of the skirt to further aid in supporting the caster. The bracket has an outwardly extending flange which carries the caster pivot shaft with a caster wheel being pivotally supported on the shaft.

In a preferred form, the caster assembly also has a provision by which it cannot drop off the skirt even when the skirt is raised to space the caster above the floor. Specifically, this can be accomplished by a groove extending along the upstanding flange of the bracket which receives a ridge on the skirt. The ridge heretofore has been employed to receive a bumper ring so that no special design of the skirt is required to accommodate the bracket. When the bracket is assembled With the skirt and the skirt ridge is nesting with the groove, the bumper ring can be placed around the skirt over all of the bracket flanges, thereby urging the flanges toward the skirt ridge and enabling the brackets to be held on the skirt even when the machine is raised. 7

While the caster assemblies are particularly advantageous for use with a floor scrubbing machine as discussed above, they have equal usefulness for other applications wherein a load is desired to be moved on casters with the caster assemblies then removed when the load is to be stationary.

It is, therefore, a principal object of the invention to provide an improved caster assembly for enabling casters to be easily attached to and removed from a load to be supported.

Another object of the invention is to provide a caster assembly by means of which casters can be readily attached to and detached from a floor scrubbing machine when the weight of the machine is to be supported independently of a scrubbing brush or tool carried thereby.

A further object of the invention is to provide an improved caster assembly having the advantages discussed above.

Many other objects .and advantages of the invention will be apparent from the following detailed description of a preferred embodiment thereof, reference being made to the accompanying drawing, in which:

FIG. 1 is a view in perspective of a floor machine with caster assemblies embodying the invention attached to a skirt thereof;

FIG. 2 is .an enlarged, fragmentary view, in elevation, with parts broken away and with parts in section, of a skirt of the floor machine with casters afiixed thereto, and with a brush shown in dotted lines; and

FIG. 3 is a further enlarged view in perspective of one of the caster assemblies shown in FIG. 2.

Referring particularly to FIG. 1, a floor cleaning machine indicated at 10 includes a skirt 12 on which is mounted a drive motor 14 having a shaft extending centrally through the skirt and engageable with a brush 16 located therebelow. The brush can consist of a suitable backing board 18 in which bristles 20 are mounted. The backing board 18 preferably is connected to the drive shaft of the motor 14 in a manner such that the brush will be driven by the shaft but can move or float vertically relative thereto, in a manner well known in the art. A suitable handle 22 extends from an edge portion of the skirt 12 with wheels 24 located at the bottom of the handle, the wheels being retractable if desired. These are employed to transport the machine 10 between the storage location and the area to be cleaned.

When cleaning most surfaces, the entire weight of the machine is allowed to be borne by the brush 16 and the bristles 20 thereof. This enables the machine to place greater pressure on the bristles and provide a more effective or stronger cleaning action. If the machine .10 is employed to clean carpeting, for example, the brush 16 will usually have much softer or flexible bristles and, in such an instance, it is desirable that the weight of the machine be supported independently of the brush and the bristles. Heretofore, casters have been employed with cleaning machines when used for carpeting and the like but such casters have been simply aflixed to the skirt by bolts, machine screws, or similar fasteners. This meant that the skirt had to be specially made to receive the bolts or screws, being drilled and possibly tapped. This also left openings when the casters were not used through which water might be ejected during a scrubbing operation. Further, the attachment of the casters to the skirt and the removal thereof was relatively time consuming with each caster usually having at least two fasteners to effect the attachment; also, tools were required and the fasteners were constantly being subject to becoming lost.

In accordance with the instant invention, a caster assembly indicated at 26 is employed. The caster assembly 26 needs no holes at all in the skirt to effect assembly and, further, the caster assembly is assembled with the skirt 12 simply by being slipped on, without any fas teners to be screwed on unscrewed.

As shown particularly in FIG. 3, the caster assembly 26 constitutes a supporting bracket 28 and a caster 30. The supporting bracket 28 includes an upstanding flange 32 which lies adjacent the outer surface of the edge of the skirt 12, as shown in FIG. 2, when assembled, and bears against the skirt when carrying the weight of the machine. The bracket 28 further includes a pair of tabs 34 at each end of the flange 32 which extend rearwardly of the flange 32 having a web portion 36 extending under the edge of the skirt 12 and a rear ear portion 38 extending up the rear or inner surface of the skirt 12.

Between the tabs 34 is a caster flange 40 extending generally radially outwardly from the skirt, when assembled, in a direction opposite to the tabs 34. An outer end portion 42 of the flange 40 contains a threaded opening which receives .a threaded shaft 44 of the caster 30. A ball bearing 46 is located at the bottom. of the shaft 44 which pivotally receives a yoke 48 of the caster. An axle 50 is carried by legs 52 of the yoke and rotatably supports a caster wheel 54. The ball bearing 46 enables the yoke 48 to pivot relative to the shaft 44 so that the machine can be easily moved about in any direction on the surface being cleaned. The caster flange 40 is sufficiently long to enable the wheel 54 to clear the brush 16 for any position of the yoke 48.

With the shaft 44 being threaded, it can be turned relative to the flange portion 42 to vertically adjust the caster 30. When in a desired position, a jam nut 54 is tightened on the flange portion 42 to hold the shaft securely in place. The adjustment thus enables the machine to compensate for wear of the bristles 20 and enables the machine to clean more effectively carpets of different pile thicknesses and heights, for example.

The skirt 12 of many floor cleaning machines has a peripheral ridge 56 extending therearound to add rigidity to the skirt and particularly to aid in maintaining a resilient bumper ring 58 thereon to protect furniture and adjacent surfaces during a cleaning operation. The ridge 56, as shown, is stamped in the skirt but in heavier and particularly cast skirts, the ridges can be cast therein. With skirts having the ridges, a ridge 60 is formed longitudinally of the upstanding flange 32 to produce a rear groove 62 fitting over the ridge 56, as shown in FIG. 2. The bumper ring 58 is then slipped over the flange 32 and the ridge 60 to hold the groove 62 in nesting relationship with the skirt ridge 56. Consequently, when the machine is tilted or otherwise spaced from the surface being cleaned, the caster assemblies 26 will remain on the skirit and not fall off.

It will be seen from the above that assembling the casters with the skirit is a quick and simple operation. For this purpose, the handle 22 can simply be tilted back on the wheels 24 toward a horizontal position to raise the skirt 12. The casters are then placed on the skirt at the desired position by placing the upstanding flanges 32 at the outer surface of the skirt and inserting the tabs 34 over the skirt edge. The bumper ring 58 is then placed over the flanges 32 to hold the caster assemblies in place.

I claim:

1. A floor cleaning machine for cleaning carpets and the like comprising a skirt, said skirt having an outwardly extending peripheral ridge near the lower edge thereof, a revolvable brush rotatably supported under said skirt, said brush being connected for floating movement relative to said skirt, a plurality of detachable caster assemblies for at least partly supporting said machine, each of said assemblies comprising a supporting bracket having an upstanding flange lying adjacent the outer surface of the skirt, said upstanding flange having a recess receiving said ridge, a tab extending under the edge of said skirt and upwardly along the inner surface thereof, a caster flange extending outwardly from said upstanding flange in a direction opposite said tab, a shaft carried by said caster flange, a caster pivotally supported by said shaft, and a resilient band extending around said skirt and outside of the upstanding flanges of said caster assemblies to hold said upstanding flanges in cooperation with said skirt ridge even when the machine is lifted.

2. A floor cleaning machine for cleaning carpets and the like comprising a skirt, said skirt having an outwardly extending perpheral ridge spaced above the lower edge thereof, a revolvable brush rotntably supported under said skirt, said brush being connected for floating movement relative to said skirt, a plurality of detachable caster assemblies for at least partly supporting said machine, each of said assemblies comprising a supporting bracket having an upstanding flange to fit over the outer surface of the skirt, said flange having a curved portion forming an outer convex surface and an inner recess receiving said ridge, a pair of U-shaped tabs extending rearwardly from a lower portion of said bracket and extending upwardly along the inner surface of said skirt, a caster flange extending outwardly from said upstanding flange in a direction opposite said tabs and located between said tabs, a caster pivotally supported below said caster flange, and a resilient bumper band extending around said skirt and fitting over the convex surfaces of said upstanding flanges to hold said flanges in nesting cooperation with said skirt ridge, even when the machine is lifted and the casters are above the floor.

References Cited UNITED STATES PATENTS 2,316,805 4/ 1943 Overholster 15-49 2,874,396 2/1959 Smith 15-49 3,068,503 1-.2/ 1962 Jepson et a1. 15-49 FOREIGN PATENTS 209,759 1/ 1956 Australia. 297,644 9/ 1928 Great Britain. 339,189 12/ 1930 Great Britain.

EDWARD L. ROBERTS, Primary Examiner.

U.S. Cl. X.R. 1630 

